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Fantastic, adj.
1. conceived or appearing as if conceived by an unrestrained imagination;
2. fanciful or capricious, as persons or their ideas or actions;
3. imaginary or groundless in not being based on reality;
4. extravagantly fanciful;
5. incredibly great or extreme; exorbitant;
6. highly unrealistic or impractical; outlandish;
7. Informal. extraordinarily good.
[Origin: 1350-1400; ME fantastik pertaining to the imaginative faculty < ML fantasticus, var. of LL phantasticus < Gk phantastik